In subterranean oil reservoirs the oil is often present in zones or layers. There are many factors, such as voids, fractures etc. which may lead to a fluid loss and complicate the recovery of the oil. Thus the recovery of oil will be largely affected by the heterogeneity of rock such a high permeability channels, voids and fractures. When fluids, such as water, flow through the oil reservoir consisting of rock of varying permeability, a higher percentage of the fluid tends to flow in the sections with higher permeability.
It would be desirable to control or prevent the passage of fluid through a portion of a subterranean formation and/or isolate specific areas in a subterranean formation or a wellbore. Similarly, in water systems or sewer drains etc. it would be desirable to be able to plug any leakages in a simple and cost-effective manner.
Hydrolyzed polyacrylamide (HPAM) has been applied to block high permeability channels and fractures due to its low price and high efficiency in blocking the high permeability channels and fractures by crosslinking with a chromium compound (Seright, R. S. & Recovery, P. An Alternative View of Filter-Cake Formation in Fractures Inspired by Cr (III)-Acetate-HPAM Gel Extrusion, SPE Journal 18, 65-72 (2003). However, with high efficiency in blocking, HPAM also blocks the pores inside the rock in an oil field. As a result oil recovery will become less efficient due to decreasing permeability of the pores.
WO 2007/141519 A2 discloses silicone-tackifier matrixes and methods of use thereof by providing a treatment fluid that comprises a base fluid and a silicone-tackifier matrix composition that comprises at least one silicone polymer component, at least one tackifying agent, and at least one curing agent and/or at least one cross linking agent, placing the treatment fluid in a subterranean formation, and allowing the silicone-tackifier matrix to form at least one silicone-tackifier matrix therein.
WO 2007/010210 discloses a method of servicing a wellbore in contact with a subterranean formation comprising placing a sealing agent and a nonaqueous carrier fluid in the wellbore, placing a nonaqueous activating fluid in the wellbore, and contacting the sealing agent with the nonaqueous activating fluid to form a sealant composition.
WO 2008/009957 discloses a method of forming a barrier for a fluid in a subterranean area penetrated by a wellbore, comprising depositing of particulate material in a fracture, wherein the particulate material comprises at least some particles made from material that swells when contacted with said fluid.
US 2008/0017376 discloses a method of reducing fluid loss in a subterranean formation comprising placing a lost circulation composition comprising a base fluid and a swellable elastomer and allowing the swellable elastomer to swell upon contact with a fluid.
US 2006/234871 A1 discloses a sealant composition for servicing a wellbore comprising at least one gel system, a leak off prevention material and water.
U.S. Pat. No. 4,649,998 discloses a method of treating a subterranean, unconsolidated sand and petroleum containing formation penetrated by at least one well, which is in fluid communication with at least a portion of the unconsolidated sand containing subterranean formation, in order to form a flexible, permeable barrier around the well which restrains the movement of sand particles into the well while permitting the passage of formation fluids including petroleum there through.
Various attempts have been made to reduce fluid loss in a subterranean formation. However, there is still a need in the art for a composition efficient for sealing leaks or fractures in a wall or formation such as a well bore, drain or pipeline. Moreover there is a need for a composition providing an efficient and cost-effective control or prevention of leakage from e.g. a subterranean formation and providing a fracture plug capable of withstanding the harsh conditions experienced in the oil drilling industry but which does not leak into the pores of a subterranean formation. Moreover, there is a need in the art for a method whereby it is possible to obtain a plug flow of the treatment fluid to the desired place in a fracture-containing system.